The liquid crystal display device and the mobile phone system are connected by a connector. In the lighting inspection/cell phone assembly process, due to the inadequate education of operating, careless operator, or the connector not clearly identified, reverse insertion of the connector is apt to occur. If estimated only based on the appearance, many connectors (especially the crimp connector) in the state of reverse insertion are basically same to those in the state of regular insertion. Power up operation in the state of reverse insertion may cause a signal loading error, which can easily cause circuit burnout.
Similarly, in other areas of electrical engineering, the reverse insertion of the connector can also cause signal loading errors, producing a great harm to the circuit system.